We have investigated the formation of amorphous and microcrystalline alloys of Pd-Si and Ti-Pd. In order to allow comparison of the two methods, both liquid quenching (LQ) for rapid solidification and mechanical alloying (MA) techniques were employed. Characterization of the materials was obtained through X-ray diffraction and differential thermal analysis (DTA).
Both the LQ and MA syntheses yielded amorphous Pd80Si20 alloys, with very similar X-ray line widths and crystallization temperaiures. However, the MA alloys contained as minority component a second phase, indexed to Pd3Si.
Quite different results were obtained for the Ti-Pd alloys. LQ splats containing 42, 66, and 80 at % Ti were not amorphous but microcrystalline, as might be expected from the very similar atomic radii of Ti and Pd. In contrast, a broad range of amorphicity, from approximately 42 to 85 at % Ti, was found in the MA synthesized materials. Overall, these results show that the two methods, LQ and MA, differ in the mechanisms of amorphization. This conclusion is further supported by additional MA and LQ experiments on ternary Ti-Pd-Cu alloys.